# Hierarchical instanced static mesh component crashing after upgrade to 4.12 **URL:** \ **Category:** Asset Creation\ **Tags:** Hierarchical-Instanced-Static-Mesh, unreal-engine, crash, question, Blueprint\ **Created:** [June 7, 2016, 7:51am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923 "2016-06-07T07:51:12Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Jaatuli](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Jaatuli](https://forums.unrealengine.com/u/Jaatuli)\ **Post date:** [June 7, 2016, 7:51am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/1 "2016-06-07T07:51:12Z")
After project was upgraded to 4.12 opening a blueprint that contains Hierarchical Instanced Static Mesh component will result in a crash. From the log I this is the important part: ``` Assertion failed: InComponent->InstanceReorderTable.Num() == InComponent->PerInstanceSMData.Num() [File:D:\Build\++UE4+Release-4.12+Compile\Sync\Engine\Source\Runtime\Engine\Private\HierarchicalInstancedStaticMesh.cpp] [Line: 756] ``` Removing the component before upgrade will fix the problem. I re-added the component and re-set the nodes exactly like they were and everything works now. ---
**Author:** ![anonymous\_user\_550b73f9](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_550b73f9](https://forums.unrealengine.com/u/anonymous_user_550b73f9)\ **Post date:** [June 7, 2016, 9:20am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/2 "2016-06-07T09:20:40Z")
Hi, thanks for the bug report report. I’ve entered ticket UE-31702 to fix the issue. Is the content small enough to upload? An easy reproduction case would be very helpful if you have one. Thanks ---
**Author:** ![Jaatuli](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Jaatuli](https://forums.unrealengine.com/u/Jaatuli)\ **Post date:** [June 7, 2016, 10:37am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/3 "2016-06-07T10:37:32Z")
The content is quite big, but the blueprint is basically a crane that add/removes chain links when moving down/up. ![93698-instancedmesh.png](https://d3kjluh73b9h9o.cloudfront.net/original/4X/d/c/f/dcfd25ba62365cb2f6476663b18319c0c67150c2.png) Component settings are default except for selecting the link mesh and setting collision to nocollision. If you can’t replicate the the bug, I’ll try to create a test project at some point when I have the time. ---
**Author:** ![anonymous\_user\_cf3d4379](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_cf3d4379](https://forums.unrealengine.com/u/anonymous_user_cf3d4379)\ **Post date:** [June 8, 2016, 1:36pm UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/4 "2016-06-08T13:36:17Z")
I have tried to reproduce this with a simple blueprint which adds an instance in its construction script, but it opened fine in 4.12. Would you be able to upload a cut-down version of your 4.11 project we could reproduce it with? ---
**Author:** ![Jaatuli](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Jaatuli](https://forums.unrealengine.com/u/Jaatuli)\ **Post date:** [June 10, 2016, 9:23am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/5 "2016-06-10T09:23:54Z")
Can you give me a email address? I need to give specific access, since the content is confidential. ---
**Author:** ![anonymous\_user\_cf3d4379](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_cf3d4379](https://forums.unrealengine.com/u/anonymous_user_cf3d4379)\ **Post date:** [June 10, 2016, 9:33am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/6 "2016-06-10T09:33:43Z")
gareth dot martin at epicgames dot com Please include a link to this thread in the email. Thanks! ---
**Author:** ![Jaatuli](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Jaatuli](https://forums.unrealengine.com/u/Jaatuli)\ **Post date:** [June 10, 2016, 9:52am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/7 "2016-06-10T09:52:12Z")
Hi, I sent you the link. I cannot add the link unless I force everyone to register to OneDrive with the email given. Crash will occur when opening the BP\_AutoCrane ---
**Author:** ![anonymous\_user\_cf3d4379](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_cf3d4379](https://forums.unrealengine.com/u/anonymous_user_cf3d4379)\ **Post date:** [June 10, 2016, 10:15am UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/8 "2016-06-10T10:15:01Z")
Thanks! I’ve received it and attached it to our internal bug report. I’ll take a look at it as soon as I can. It’s so much easier to fix when I have a repro project 🙂 ---
**Author:** ![anonymous\_user\_cf3d4379](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_cf3d4379](https://forums.unrealengine.com/u/anonymous_user_cf3d4379)\ **Post date:** [June 10, 2016, 6:24pm UTC](https://forums.unrealengine.com/t/hierarchical-instanced-static-mesh-component-crashing-after-upgrade-to-4-12/359923/9 "2016-06-10T18:24:58Z")
Thanks very much I got a chance to look into it today and it should be fixed for 4.12.3!